Concentration of chlorophyll-a is an adequate parameter for assessing the trophic state in the summer. So, check the photosynthetic content of pigments as a bioindicator of chlorophyll-a,b,c were studied in six stations of Gomishan international wetland and a sea station. Furthermore were investigated the qualitative evaluation of trophic state of the wetland and its dynamics. Phytoplankton samples after the filtration were extracted in 90% acetone, and were obtained the absorption of pigments in Spectrophotometer. In addition to chlorophyll, were measured the water temperature, dissolved oxygen, pH, salinity, turbidity and depth. Based on results, the increasing concentrations of chlorophyll-a in September showed the trophic level was hypertrophic and occurred the cyanobacterial bloom. The statistical results showed log Chl-a a positive significant correlation with water temperature, dissolved oxygen and salinity (p<0.01). Also in the Gorganrud estuarine (S2) was measured the diatom bloom as pollution indicator in July. The Gomishan coastal wetland on one hand affected by the human activities in adjacent areas and the other hand under is the influence of global warming on a large scale and in its catchment area, that causing the intensity of evaporation, salinity and become its shallow. Accordingly, improving circulation of wetland water and connection with the sea, improving future guidelines on the estuarine management, reduce and control of urban wastewater and aquaculture wastewater filtration is suggested.